Neutron Activation Analysis of Nitrogen in Feedstuffs

Abstract

Abstract The application of neutron activation analysis to the determination of nitrogen in various feeds and feedstuffs has been investigated. Samples were bombarded with fast neutrons to induce the 14N(n, 2n)13N reaction. 13N is a positron emitter with a 10 min half-life. The positrons annihilate in or near the sample to produce 0.51 MeV gamma rays, which are then counted in a detector system. Phosphorus and silicon interfere and are compensated for in the technique. A total of 419 individual runs were made on 53 samples covering 16 different types of materials. Total analysis time was 15 min per sample with a production rate of 12 samples per hr. The coefficient of variation of runs by the automated method typically ranged from 0.90 to 1.73 on the different sample groups. A good correlation between protein determined by the Kjeldahl technique and that determined by the automated method was demonstrated.